Plugin allows you to manually crop all the image sizes registered in your WordPress theme (in particular featured image).
Generate thumbnails on demand and store them in WordPress' uploads directory for future requests.
NextGEN Image Cropper extends the NextGen Gallery plugin to allow cropping of images.
NextGEN Z Cropper is a plugin that resizes and crops(!) your pictures while uploading them (not only thumbnails!). If the picture does not match your
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